Multimedia Encyclopedia

Sarcoidosis

Sarcoidosis is a disease in which inflammation occurs in the lymph nodes, lungs, liver, eyes, skin, or other tissues.

The exact cause ofsarcoidosisis unknown. What is known is that when a person has the disease, tiny clumps of abnormal tissue (granulomas) form in certain organs of the body. Granulomas are clusters of immune cells.

The disease can affect almost any organ of the body.It most commonly affects the lungs.

Doctors think that with sarcoidosis, persons have genes that make it easy for them to develop the disease. Things that may trigger the disease include infections with bacteria or viruses. Contact with dust or chemicals may also be triggers.

Thedisease is more common in African-Americans and Caucasians of Scandinavian heritage. More women than men have the disease.

The diseaseoften begins between ages 20 and 40. Sarcoidosis is rare in young children.

A person with a close blood relative who has sarcoidosis is nearly five times as likely to develop the condition.

Symptoms

There may be no symptoms. When symptoms occur, they can involve almost any body part or organ system.

Outlook (Prognosis)

Many people with sarcoidosis are not seriously ill, and they get better without treatment. Up to half of all persons with the disease get better in 3 years without treatment. Persons whose lungs are affected may develop lung damage.

Overall death rate from sarcoidosis is less than 5%. Causes of death include:

Sarcoid, stage I - chest X-ray - illustration

Sarcoid is primarily a lung (pulmonary) disease. In the early stages, a chest film may show enlargement of lymph nodes in the center of the chest near the heart (mediastinum).

Sarcoid, stage I - chest...

illustration

Sarcoid, stage II - chest X-ray - illustration

Sarcoid causes damage to the lung tissue that heals by scarring. The film shows a diffuse milky and granular appearance in the normally dark lung areas. This individual has marked decrease in lung function.

Sarcoid, stage II - ches...

illustration

Sarcoid, stage IV - chest X-ray - illustration

This film shows advanced sarcoid, scarring of the lungs (the light streaking), and cavity formation (the dark areas in the upper right side of the picture).

Sarcoid, stage IV - ches...

illustration

Sarcoid - close-up of the skin lesions - illustration

Sarcoid - close-up of the skin lesions: 20 to 25 percent of individuals with sarcoidosis have skin manifestations as seen in this picture. The extent of the skin manifestations is difficult to predict, but the most common are red papules that are translucent as seen here.

Sarcoid - close-up of th...

illustration

Erythema nodosum associated with sarcoidosis - illustration

This picture shows reddish-purple, hard (indurated), painful nodules (Erythema nodosum) that occur most commonly on the shins. These lesions may be anywhere on the body and may be associated with tuberculosis (TB), sarcoidosis, coccidioidomycosis, systemic lupus erythematosis (SLE), fungal infections, or in response to medications.

Sarcoidosis - close-up - illustration

Sarcoidosis - close-up

Sarcoidosis on the elbow - illustration

These lesions of sarcoidosis are located on the elbow and are red, elevated patches (plaques). The cause of sarcoidosis remains unknown.

Sarcoidosis on the elbow

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Sarcoidosis on the nose and forehead - illustration

These are sarcoid lesions on the face. These lesions often appear in scars, as is seen in this photograph.

Sarcoidosis on the nose ...

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Respiratory system - illustration

Air is breathed in through the nasal passageways, travels through the trachea and bronchi to the lungs.

Respiratory system

illustration

Sarcoid, stage I - chest X-ray - illustration

Sarcoid is primarily a lung (pulmonary) disease. In the early stages, a chest film may show enlargement of lymph nodes in the center of the chest near the heart (mediastinum).

Sarcoid, stage I - chest...

illustration

Sarcoid, stage II - chest X-ray - illustration

Sarcoid causes damage to the lung tissue that heals by scarring. The film shows a diffuse milky and granular appearance in the normally dark lung areas. This individual has marked decrease in lung function.

Sarcoid, stage II - ches...

illustration

Sarcoid, stage IV - chest X-ray - illustration

This film shows advanced sarcoid, scarring of the lungs (the light streaking), and cavity formation (the dark areas in the upper right side of the picture).

Sarcoid, stage IV - ches...

illustration

Sarcoid - close-up of the skin lesions - illustration

Sarcoid - close-up of the skin lesions: 20 to 25 percent of individuals with sarcoidosis have skin manifestations as seen in this picture. The extent of the skin manifestations is difficult to predict, but the most common are red papules that are translucent as seen here.

Sarcoid - close-up of th...

illustration

Erythema nodosum associated with sarcoidosis - illustration

This picture shows reddish-purple, hard (indurated), painful nodules (Erythema nodosum) that occur most commonly on the shins. These lesions may be anywhere on the body and may be associated with tuberculosis (TB), sarcoidosis, coccidioidomycosis, systemic lupus erythematosis (SLE), fungal infections, or in response to medications.